Control apparatus



Feb. 5, 1929.

E. L. HOUGH CONTROL APPARATUS Filed Oct. 16, 1926 Fig.1.

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UNITED sTATEs PATENT oEFicE.

EUGENE L. ROUGH; E SCHENECTADY, NEW YORK, ASSIGNOR' TO GENERAL ELECTRIC .COMPANY, CORPORATION NEW YORK.

- common APPARATUS.

Application filed October 16, 1926.

My invention relates to control apparatus, and has for its principal object the provision of an improved apparatus for controlling the operation of a vapor electric device suchas 6 a-mercury arc rectifier arranged. to be connected between alternating and =direct current circuits. i Y I It is desirable that the temperature of a mercury rectifier be above a predetern'rined value when its operation is started, that this temperature be maintainedwithin predetermined limits during the operation ofthe rectifier, that the rectifier be deenergized if its temperature becomes excessive, and thatthere be produced and'maintained in the vicinity of the rectifier cathode a supply of ionized vapor which facilitates the transmission of load current between the main cathode and the main anodes of the rectifier. In accordance with my invention, these and other 'results are effected ini'esponse to energiiation of a temperature control elementsubjected to substantially the same temperature as the recti- My invention. wil;l bebetter understood from the following. description when considered in' connection with the accompanying drawings audits scopewill be pointed-out in .the appended cla:i rns Y Referring-toi'thedrawings, Fig. '1 illustrates a controlapparatus wherein iny invention has been embodied and Fig. 2 -illus-.

trates certain details 'in-tli'e arrangement and construction of this-apparatus, 4

Fig. 1 shows an alternating current circuit 1 and a direct current. circuit-2, which are arranged to be interconnected through means comprising a smoothing reactor 3, a mercury arc rectifier 4, a main circuit breaker 5 and amain transformerfi, which-includes a primary winding 7 and secondary windings 8- and 9. The rectifier {i comprisesinain anodes 10, which are connected to'the end terminals of the winding 8, a mercury cathode .11, which is connected t-hrougha switch operat- 'ing coil 12,- an indicating;.Zdevice 13, the

smoothing reactor? 3, and a ,load Mat-o the Win ng 8 at afpointinte mediateitS ends, and exciting electrodes '16, which are connected to the cathode 11 through 0 posite halves of .a transformer 17 supplied current from f the secondary winding 9. Shaking-or tilting oftheirectifier'to establish an exciting are between the cathode 11 with Serial No. 142,104.

and the existing anodes 16 is effected 'l'iy rocking the rectifier about a pivot 17. This result is produced through a. solenoid comprising an operating coil 18 and a core 19', which is mechanically connected to therectitier through members 20 and 21 and is biased to its illustrated position by a spring-22.

Q As indicated by" Fig. 2, the rectifierf4 is submerged in a fluid 23,'su ch as oil, contained in a vessel 2 A mixer 25 operated by a motor 26 is prot'ided for equalizingthetemperature of this fluid at various points within the vessel. This ten'iperature is regulated by a coolingmedium circulated througl a coiled pipe 27 and by a heating element 28. Control of the heater 28 and a valve 29 through which the cooling medium isadmitted to the coil'27 is effected by meansof a thermostatic element 30 mounted'within the tank 24. Also mounted within the vessel 2i are a thermostatic element 31,- which causes the circuit breaker 5 to be closed whenthe'temperature of the rectifier has attained a predetermined-value and a thermostatic element 32 'which causes the circuit breakei 'fi to be opened when the temperature oftherec'tifier becomes too lii gh..for.- .sae.. operation. Current for operating the control eqnipnient ofthe apparatus issupplicd fromthe alter mating current linev 1 through switches- 33 and 34. v I

{\ssuuung the, line 1 to beenergizcd. the

switches 33 and 34. to "be closed, and the other parts of the. apparatus to be as illus 'tratcd, current-is supplied "to the heater 2h.

\Vhcu the heater Lb has raised the temperature of the rectifier to a predctermiued value, the thermostatic element 311s operated into engagement with a contact 38,.thus connecting a closing coil 39 of the breaker 5 m the line l through an auxiliary contact-i0 and causing this-breakerto be operated to its closed position. Under these conditions'current is supplied tothe operating coil: 35 of a switch 36 \vhichis operated to its upper closed position instantaneouslicpnd opens after' a time delayv determine 7 b -a timi g element 37, the shaker opera.ting'"co il 18 is connected to the line'l through the auxiliary contact 40an'd the switch 36, the rectifieris tilted in a manner to produce temporary contact between the cathode 1.1 and the exciting electrodes 16, and the exciting arc of the rectifier is established, thus energizing the operating coil 12 of a switch 41 and deenergizing both the operating coil 35 of the switch 36 and the shaker operating coil 18.

During operation of the rectifier, opening of the main circuit breaker 5 may be produced either by a trip coil 42 which is suplied with current from a current transtormer 43 connected in the supply line of the rectifier 4 -or by'a trip'co il 44 which is arranged to be connected to the line 1. through the thermostatic element 32, through a switch 45, or through a switch 46, which is arranged to close if the shaker operating coil is not deenergized within a time interval determined by a timing element 47. The thermostatic element 30 is so arranged that it is in its illustrated position whenthe' rectifier temperature is too low, is in its mid or neutral position when the temperature of the rectifier is normal, and is in engagement with a contact 48 when the temperature of the rectifier is too high. When the thermostatic element engages the contact 48 a circuit is completed between the circuit 1 and an operating coil 49 which controls, the opening of the valve 29 through which the cooling medium is admitted to the coil 27.

Arectifier thus has its temperature regulated by the thermostatic element 30, is pro...

tected against overheating by the thermo static element 32, is protected against exces sive load by the trip coil 42, is protected againstfailure of its exciting are by switches 41 and 36, and is protected against undue delay in the starting of the exciting are by the switch 46.

The embodiment of the invention illustrated and described herein has been selected forthe purpose of clearly setting forth the principles involved, It will be apparent, however, that the invention is susceptible of being modified to meet the different conditions encountered in its use, and I therefore aim to cover by the'appended claims all modilications within the'true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is 1. The combination of an alternating current circuit, a vapor electric device comprising an anode and a cathode and provided with an exciting electrode arranged to produce a supply of ionized vapor in the vicinity of said cathode, means for regulating the temperature of said rectifier, and means operable at a predetermined value of said temperature to connect said anode to said circuit and to establish an are between said cathode and said exciting. electrode.

2. The combination of an alternating current circuit, a'vapor electric device comprising an anode and a cathode and provided with an exciting electrode arranged to produce a supply of ionized vapor in the vicinitv of said cathode, means for regulating the temperature of said rectifier, means operable at a predetermined value of said temperature to connect said anode to said circuit and to establish an are between said cathode and said exciting electrode, and means operable to disconnect said anode from said circuit in response to a predetermined rise in said temperature.

3. The combination of an alternating current circuit, a vapor electric device comprising an anode and a cathode and provided with on exciting electrode arranged to produce a supply of ionized vapor in the vicinity of said cathode, means for regulating the temperature of said rectifier, means operable at a predetermined value of said temperature to connect said anode to said circuit and to establish an are between said cathode and said exciting electrode, and means operable to disconnect said anode from said circuit if said exciting are is not established within a predetermined interval of time after the connection of said anode to said circuit.

4. The combination of an alternating current circuit, a vapor electric device comprising an anode and a cathode and provided with an exciting electrode arranged to produce a supply of ionized vapor in the vicinity of said cathode, means for regulating the temperature of said rectifier, a switch arranged to connect said anode to said circuit, means operable to produce closure of said switch and to produce temporary contact between said cathode and 'said exciting electro e at a predetermined value of said tempe'rature,' and means operable to break said contact when an eXcitIng are is established between said cathode and exciting electrode.

5. The combination of an alternatingcurrcnt circuit, a vapor electric device comprising an anode and a cathode and provided with an exciting electrode arranged to produce a supply of ionized vapor in the vicinity of said cathode, means for regulating the temperature of said rectifier, a switch arranged to connect said anode to said circuit, means operable to produce closure ..of said switch and to produce temporary contact between said cathode and said exciting electrode at a predetermined value of said temperature, means operable to break said .contact when an exciting arc is established between said cathode and exciting electrode,

and means operable to'disconnect said anode from said circuit if said exciting are is not established within a predetermined time in terval after the connection of said anode to said circuit.

Inwitness whereof, I have hereunto set my hand this 15th day of October, 1926.

EUGENE L. HOUGH. 

